This, for me, sums it up best.
You
cannot stop hyper-extension. I'm not completely sure, but if I get it correctly a double-jointed joint can only be extended fully (beyond 180degrees) with external force. The joint mechanism can take it only to 180degrees as in a normal joint. As such, the arm
does change sinuosity during bowling, but it goes from, say, 178degrees to 192degrees (the latter angle which is beyond a normal elbow). The arm of a chucker would, for instance, go from 152degrees to 176degrees (hypothetical figures).
I see nothing wrong with a bowler who has a double-jointed elbow bowling in cricket, and nor do most people. Some, of course, don't accept optical-illusions, and people like Shoaib and Kirtley (had never seen Rutra Pratap Singh before yesterday, and confess I noticed nothing yet)
do look bad, but it's merely illusion.
No, it didn't come into that: the point of that was that the ideals - that most bowlers had bowling-actions where the elbow flexation was 0 degrees - were false, and most bowling-actions involved 10 degrees flexation or something around about (there was, obviously, quite a bit of variation - which is not really surprising given how many different bowlers there are).
Then the ludicrousy of stating that 14 degrees was somehow massively different from 16 degrees, while there was no difference between 12 and 14, came in.
